In Imperial Russia a person of simple birth could be granted "personal nobility"(non-hereditary), by state service or even by some noble deeds out of it (traders got it this way).
The whole system of ranks was copied by Peter I at the beginning of the 18th century, as far as I know. The rank system set a range of ranks at which a person was granted personal nobility automatically. (English wiki article on the subject is very weak)
But what countries served as the source of the system? In what European countries (and where) did such "non-hereditary nobility" exist? What terms were used for it?
I am not talking about the difference of titled aristocracy ( with hereditary titles or not) and non-titled nobility, but about the border between the lower layer of nobility and simple people.
It seems, the
Persönlicher Adel, mentioned by @nvoigt, is the most close term. But what was the first? And Germany was not a single state then. Where exactly that term appeared? Or was Peter I the author of that social invention?